Subsecond dopamine (DA) concentration transients have previously been observed in behaving rats. Here, we demonstrate for the first time that DA transients can be pharmacologically induced in anesthetized rats. Coadministration of the D2 receptor antagonist, haloperidol, and the DA uptake inhibitor, nomifensine, results in significantly more DA transients than either drug alone. The results show that both D2 autoreceptors and the dopamine transporter regulate subsecond DA neurotransmission.